HSG250 Permit-to-Work Guidance: A Plain-English Guide

If you have ever set up or reviewed a permit-to-work system in the UK, someone has probably told you to "check HSG250." It is the HSE's main guidance document on permit-to-work systems, and it is the benchmark against which most PTW systems are judged. Yet surprisingly few people have actually read it cover to cover. The HSG250 permit to work guidance is only about 40 pages, but it is written in a style that can be hard going if you just want to know what you need to do.

This guide translates HSG250 into practical terms. What does it actually say? What does it require? And where do people most commonly get it wrong?

You can download HSG250 from the HSE website (it is officially titled "Guidance on permit-to-work systems"). If you are not sure what a permit-to-work system is in the first place, our introductory guide covers the basics.

What Is HSG250?

HSG250 is a guidance document published by the Health and Safety Executive. It is not legislation — it does not have the force of law in the way that the Management of Health and Safety at Work Regulations 1999 or the Confined Spaces Regulations 1997 do. However, it represents the HSE's view of good practice, and courts regularly treat HSE guidance as the standard against which employers are measured.

Put simply: if your permit system follows HSG250, you are on solid ground. If it does not, you need a good reason why.

HSG250 applies across all industries, not just construction. It covers chemical plants, oil and gas, utilities, manufacturing, and any other sector where permits are used. The principles are universal.

The Key Principles of HSG250

HSG250 is built around several core principles. Understanding these is more important than memorising the document section by section.

A permit is not a risk assessment

HSG250 makes a clear distinction: a permit authorises specific work under specific conditions, referencing a risk assessment that has already been completed. The permit does not replace the risk assessment — it confirms that the controls identified in the assessment are actually in place before work begins.

This distinction matters because some organisations try to combine the two into a single document. That can work for simple tasks, but for complex high-risk work, the risk assessment and the permit serve different purposes and should be treated separately.

Permits are for high-risk work only

HSG250 is explicit that permits should be reserved for work where the hazards are serious and the consequences of inadequate controls are severe. It warns against applying permits to low-risk tasks, because doing so devalues the system and creates "permit fatigue" — where people stop taking the process seriously because they have to fill in a permit for everything.

The guidance identifies the typical scenarios: hot work, confined space entry, electrical isolation, work on high-pressure systems, and other tasks where the risk of serious injury or fatality is real.

The permit is a communication tool

One of the most important points in HSG250 — and one that is frequently overlooked — is that a permit is fundamentally a communication tool. It ensures that the person doing the work, the person authorising it, and anyone else who needs to know are all aligned on what is being done, where, when, and under what conditions.

The dual-signature requirement (applicant and authoriser) exists to force this communication. A permit that is filled in by one person and filed without a conversation has failed in its primary purpose.

The system needs active management

HSG250 emphasises that a permit-to-work system requires ongoing management. It is not enough to create templates and issue them. Someone needs to oversee the system, monitor that permits are being used correctly, and intervene when problems arise.

This includes monitoring for:

Permits issued after work has already started
Missing or late close-outs
Checklists that are bulk-ticked rather than individually confirmed
Clashes between multiple active permits in the same area
Permits extended beyond their original validity without proper review

What HSG250 Requires in a Permit-to-Work System

The guidance describes the essential elements of a compliant system:

Clear scope

The system must define which activities require permits and which do not. This should be documented in site rules or a health and safety management plan. If you are working under CDM 2015, this information should be in the construction phase plan.

Defined roles

HSG250 identifies three key roles:

Permit applicant / holder — the person requesting and carrying out the work
Permit authoriser — the person checking conditions and authorising the work
Area authority / site controller — the person with overall responsibility for the area where work is taking place

On smaller sites, the area authority and the authoriser may be the same person. The important point is that the roles are defined and people know who is responsible for what.

Adequate training

Everyone involved in the permit system must be trained. Authorisers need to understand the hazards of the work they are authorising. Applicants need to know how to complete the permit correctly. And everyone needs to understand that starting work without a valid permit is not acceptable.

A structured permit document

HSG250 describes what a permit form should contain:

A clear description of the work and its location
The hazards identified and the risk assessment reference
The precautions required and a checklist confirming they are in place
Time limits for the permit's validity
Signatures of both the applicant and the authoriser
A close-out section confirming the work is complete and the area is safe

Our permit to work template follows this structure, and we have specialist templates for hot work, confined spaces, working at height, electrical isolation, and excavation.

An audit trail

HSG250 requires that completed permits are retained so they can be reviewed during audits or investigations. The guidance does not specify how long to keep them, but best practice is a minimum of three years — longer for work that could have long-latency health effects (such as asbestos exposure).

The audit trail should allow you to answer questions like: "What permits were active in this area last Tuesday?" and "Who authorised the confined space entry on the third floor last month?" If your filing system cannot answer these questions quickly, it is not fit for purpose.

Regular review of the system

HSG250 recommends periodic review of the entire permit-to-work system, not just individual permits. This means looking at whether the system is working as intended, whether the right activities are being covered, whether training is adequate, and whether people are actually following the process. Our permit-to-work audit guide provides a structured approach to conducting these reviews.

Common Misunderstandings About HSG250

"HSG250 is the law"

It is not. It is guidance. But it is the HSE's guidance, and deviating from it without good reason is difficult to defend. In enforcement proceedings, the HSE will reference HSG250 as the standard of good practice. If your system aligns with it, you are in a strong position. If it does not, you need to demonstrate that your alternative approach provides at least the same level of protection.

"We only need permits if HSE tells us to"

Wrong. The duty to control high-risk work comes from legislation — primarily the Management of Health and Safety at Work Regulations 1999, the Confined Spaces Regulations 1997, and the Electricity at Work Regulations 1989. HSG250 describes how permits help you meet those duties. You do not need to wait for an inspector to tell you to use permits.

"A signed permit means the work is safe"

HSG250 is careful to point out that a permit is not a guarantee of safety. It is a control measure that reduces risk by ensuring hazards have been considered and precautions are in place. But conditions can change during the work. The permit system needs to account for this — through monitoring, time limits, and procedures for stopping work if conditions deteriorate.

"Digital permits are not covered by HSG250"

HSG250 was written before digital permit systems were widely available, so it describes the process in terms that could apply to either paper or digital formats. The principles are format-neutral: structured documentation, dual signatures, audit trails, close-out procedures. A well-designed digital system meets every HSG250 requirement, and the automatic timestamping and enforced mandatory fields arguably provide stronger compliance evidence than paper. Our comparison of paper vs digital permits covers this in detail.

Putting HSG250 Into Practice

If you are setting up or reviewing a permit system and want to align it with HSG250:

Download and read the document — it is 40 pages and genuinely useful
Use our PTW readiness checker to score your current system against the key requirements
Follow our permit-to-work implementation guide for a step-by-step setup process
Train your team on both the mechanics and the purpose of the system

PermitPad is building a digital permit-to-work system aligned with HSG250 principles — structured fields, mandatory checklists, dual signatures, automatic audit trails, and formal close-out. Join the waitlist to be notified when it launches.